SDLS153A January   1981  – January 2016 SN74LS292 , SN74LS294

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Recommended Operating Conditions
    3. 6.3 Thermal Information
    4. 6.4 Electrical Characteristics
    5. 6.5 Switching Characteristics
    6. 6.6 Typical Characteristics
  7. Parameter Measurement Information
    1. 7.1 Logic Diagrams
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Related Links
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

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订购信息

1 Features

  • Count Divider Chain
  • Digitally Programmable from 22 to 2n
    (n = 31 for SN74LS292 , n = 15 for SN74LS294)
  • Useable Frequency Range from DC to 30 MHz
  • Easily Expandable

2 Applications

  • Frequency Division
  • Digital Timing

3 Description

The SN74LS29x devices are programmable frequency dividers and digital timers contain 31 flip-flops plus 30 gates (in SN74LS292) or 15 flip-flops plus 29 gates (in SN74LS294) on a single chip. The count modulo is under digital control of the inputs provided.

Both types feature an active-low CLR clear input to initialize the state of all flip-flops. To facilitate the incoming inspection, test points are provided (TP1, TP2, and TP3 on the SN74LS292, and TP on the SN74LS294). These test points are not intended to drive system loads. Both types feature two clock inputs; either one may be used for clock gating (see Table 1).

A brief look at the digital timing capabilities of the SN74LS292 shows that with a 1-MHz input frequency, programming for 210 gives a period of 1.024 ms, 220 gives a period of 1.05 sec, 226 gives a period of 1.12 min, and 231 gives a period of 35.79 min.

These devices are easily cascadable, giving limitless possibilities to achievable timing delays.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
SN74LS292N PDIP (16) 6.35 mm × 19.30 mm
SN74LS294N
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Logic Symbols

SN74LS292 SN74LS294 logic_symbol_01_SDLS153.gif